Dermatitis means an inflammation of the skin. It is commonly manifested as redness, swelling, itching. It is different from eczema as in all eczemas are types of dermatitis of some sort but all types of dermatitis are not eczemas.
There are various classifications of dermatitis. Here are the common ones:
Irritant contact dermatitis: Caused due to some irritant chemicals for example detergents, soaps, perfumes, etc. ICD is usually seen on the hands first as an inflammation in the skin with scaling. The first step to treating this condition is stopping the usage of agents causing it.
Allergic dermatitis: When the skin infection is due to an allergy or allergic reaction during which the body’s antibodies react with the allergens, it is called allergic dermatitis. The reaction is delayed and does not take place the first time your skin touches something it is allergic to. But your skin becomes sensitive to it and the next time it comes in contact with the allergen, the skin shows a reaction. Usually the immune system is also involved in this kind of dermatitis.
Atopic dermatitis: It is commonly seen in young children characterised by dry skin, itching and may even lead to eczema patches. Approximately 50% of patients develop this condition by the first year of life and additional 30% develop it within 1-5 years. Initially, it was thought that these children would outgrow this eczema by adolescence; however due to changes in our lifestyle, atopic dermatitis is seen in adults as well. Usually, the cheeks and lips are affected first in atopic dermatitis.
Seborrheic dermatitis: It is a more severe form of the common dandruff – greasy, scaly lesions seen over the scalp as well as on the chest and back and other hair bearing areas. It is more prevalent among males but usually occurs in infants within the first three months of life. Mostly affects the oily areas white to yellowish scales with or without reddened skin.
Nummular dermatitis: This results in round, coin-shaped patches on the skin (particularly where the skin is dry) but can be anywhere on the body. The patches are whitish or reddish in colour and may be itchy or crusty. This type usually affects older men but is quite uncommon. It is also not contagious.
Id eruption: It is a dermatitis that develops due to the presence of another intense inflammatory reaction somewhere else in the body e.g. fungal infections.
Pompholyx: It is characterised by deep vesicles and in some cases blisters over the hands and feet, intensely itchy lesions.
Lichen Simplex Chronicus (LSC): This is a dermatitis that happens due some long standing skin condition associated with chronic itching. The skin becomes thick. People who have anxiety disorders are prone to it.